Count back and you'll see: Jessica Ennis (center) and other competitors only went over nine hurdles. There were supposed to be 10.

Andrew Yates AFP/Getty Images

When she hit the tape Sunday at the Powerade Great City Games in Manchester, England, Britain's Jessica Ennis hadn't only beaten Olympic heptathlon champion Dawn Harper.

Ennis had also run a personal best 12.75 seconds in the 100-meter hurdles — 0.04 of a second faster than she'd ever run that race.

It was her personal best, that is, until 2004 Olympic heptathlon bronze medalist Kelly Sotherton, also of the U.K., tweeted this question:

"That 100mh was great but I'm sure that there was only 9 hurdles not 10. Please someone verify!"

Sure enough, when organizers went back to check they realized "they had neglected to set up the 10th hurdle, leaving the athletes with an extra-long run-off to the finish line," as The Telegraph writes. So, no personal record.

Ennis, a 26-year-old from Sheffield, isn't just any British athlete. She is, as The Guardian says, "the poster girl for the London Games" who has been put out front as one of the faces of the British team. After learning of the foul-up, the newspaper says she had this to say:

"I feel let down. I felt like it was a good race, I was running well, I was obviously coming through at the end, stick another hurdle on there it would have been the same outcome but, argh, I'm so annoyed. What can I say? I've still had a good competitive race but I've just not got the result that I wanted."

We assume, by the way, that this kind of thing won't be allowed to happen during the London Games, which get started in 67 days.

As for her sport, along with the 100-meter hurdles, what other events are in the two-day heptathlon?

-- High jump.

-- Shot put.

-- 200-meter sprint.

-- Long lump.

-- Javelin.

-- 800-meter race.

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